• Title/Summary/Keyword: Long cycle life

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Fatigue Test and Service Life Assessment of Steel Truss Bridges with Initial Imperfections (초기결함을 갖는 강교량의 피로시험 및 수명 평가)

  • 방명석
    • Journal of the Korean Society of Safety
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    • v.15 no.4
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    • pp.119-122
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    • 2000
  • The truss bridge is composed of numerous steel beams. In long span bridges the size of beams is getting larger, so the number of plate girders is increasing instead of rolled beams. This plate girder has long welding lines at the intersection of steel plates. The improper welding at the intersection line causes the steel bridge to be structurally unsafe. In this paper the loss of member section from improper welding was measured and the experimental testing was performed to get the S-N curve from testing models with sectional losses. The improper welding resulted in the lowering of structural safety and the shortening of life cycle.

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Life Analysis of Relays based on Life Prediction Method (수명예측 방법에 따른 계전기의 수명분석)

  • Shin, Kun-Young;Lee, Duk-Gyu;Lee, Hi Sung
    • Journal of the Korean Society of Safety
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    • v.27 no.4
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    • pp.115-120
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    • 2012
  • In order to establish preventive maintenance standards through analysis & reliability prediction of about 60,000pcs of 20kindsof relays and contractors used for Seoul subway trains, several life prediction methodologies were applied. Firstly, Occurrence, Severity, Detection were defined and predicted by applying operation characteristic of EMU to the number of actions of relays & contactors which the manufacturers generally offer as the life cycle data. Secondly, failure distribution and average life of parts were analyzed through interpretation of field data based on a lot of experience which had built up in the field for a long time. Finally, using the 217PLUS standard as a reliability prediction program, comparative analysis of use reliability and inherent reliability was done through reliability prediction at the part level and system level.

Multi-level Product Information Modeling for Managing Long-term Life-cycle Product Information (수명주기가 긴 제품의 설계정보관리를 위한 다층 제품정보 모델링 방안)

  • Lee, Jae-Hyun;Suh, Hyo-Won
    • Korean Journal of Computational Design and Engineering
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    • v.17 no.4
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    • pp.234-245
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    • 2012
  • This paper proposes a multi-level product modeling framework for long-term lifecycle products. The framework can help engineers to define product models and relate them to physical instances. The framework is defined in three levels; data, design model, modeling language. The data level represents real-world products, The model level describes design models of real-world products. The modeling language level defines concepts and relationships to describe product design models. The concepts and relationships in the modeling language level enable engineers to express the semantics of product models in an engineering-friendly way. The interactions between these three levels are explained to show how the framework can manage long-term lifecycle product information. A prototype system is provided for further understanding of the framework.

Estimation of Life Expectancy and Budget Demands based on Maintenance Strategy (도로포장 유지보수 전략에 따른 기대수명과 보수비용산정)

  • Han, Dae-Seok;Do, Myung-Sik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.4D
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    • pp.345-356
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    • 2012
  • Road pavement requires repetitive maintenance works to maintain satisfactory service level to the public. However, the repetitive maintenance works upon deteriorated pavement structure make negative effects to deterioration speed. It often leads to inefficient use of limited budget. For that reason, the pavements require reconstruction work to recover their original performance. Recently, construction demands in the Korean national highway have already been reached to maximum level, and the aged pavements start to demand much more reconstruction works. However, in the real world, road agencies have often been confused when they determine maintenance design for such aged road sections due to budget constraint. It is because there is no reliable long-term maintenance strategy that supports their decision making. To support their decision making, this paper aimed to suggest the best maintenance strategy considering changing process of pavement performance by repetitive maintenance works. As an analysis method, probability distribution and hazard function to estimate the life expectancy were adopted, and then the results were used for long-term life cycle cost analysis with deterministic or Monte-Carlo method under various scenarios. As an empirical study, the Korean national highway data that has long-maintenance history data since 1986 has been applied. Last, this paper considered quality assurance of maintenance work to improve maintenance quality. These could be important information as a part of long-term maintenance strategy of pavement.

Estrus Cycles of the Female Tscherskia triton (Mammalia: Rodentia: Cricetidae) according to the Photoperiod (광주기에 따른 비단털쥐(Mammalia: Rodentia: Cricetidae) 암컷의 발정주기 변화)

  • Park, Jun-Ho;Ahn, Keun Jae;Oh, Hong-Shik
    • Korean Journal of Environmental Biology
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    • v.35 no.2
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    • pp.160-168
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    • 2017
  • Tscherskia triton is widely distributed in Northern China, Korea, and the adjacent areas of Russia. Except its distribution, reproduction, and growth development related to life history, reproductive cycle and reproductive organs of T. triton are rarely studied in Korea. The purpose of this study was characterized the estrous cycle of T. triton captured in Jeju Island in order to provide information to a better information of captive breeding of the species when long-day (16L : 8D) and short-day (8L : 16D) photoperiod. Then, histological study of the ovaries and uterus with five females in each photoperiod was performed. The duration of the estrus cycle was 4~5 days and it showed regular cycle pattern. Results of the vaginal cytology examination showed four characteristic phase of the estrous cycle in long-day photoperiod (16L : 8D): proestrus, estrus, metestrus and diestrus. However, in short-day photoperiod, the diestrus phage of the estrus cycle was maintained from the $6^{th}$ to $12^{th}$ day. In the long-day photoperiod, females had many Graafian follicles and corpus luteums in large ovaries, and developed uterine glands in the thick endometrium. But they had some primary, secondary and tertiary follicles, and undeveloped uterine glands in the thin endometrium during short-day photoperiod. These results were identified difference of the estrus cycle and histological characteristics of reproductive tracts according to the photoperiod. These results are very important clues to the reproductive biology of T. triton, and it will be widely used as date for maintaining biodiversity.

Longitudinal Study on the Profiles of Symptom Distress and Functional Status in Gynecologic Cancer Patients Receiving Chemotherapy (항암화학요법을 받는 부인암 환자의 종단적 건강문제 변화양상 분석)

  • Chung, Chae-Weon
    • Women's Health Nursing
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    • v.12 no.1
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    • pp.53-60
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    • 2006
  • Purpose: This study aimed to explore changes in symptom distress and functional status in gynecologic cancer patients during the entire treatment cycles of chemotherapy. Methods: A prospective and longitudinal study with repeated measures was designed. Symptom Distress Scale and Karnofsky Performance Status Index were included in a daily log developed for self-administration. A total of 39 patients with a mean age of 48.4 years participated. Results: The levels of symptom distress and functional status changed significantly over the six cycles. Symptom distress kept increasing until its peak at the fourth cycle, while the functional status scored lowest at the first cycle, then it improved as the cycle repeated. In each cycle, symptom distress was marked higher during the first 6 days accompanying poor functional status. However, both changes did not recover completely until the end of each cycle. Conclusion: Nursing assessment and intervention need to be provided based on these changing patterns to help cancer patients cope and adjust successfully during the long treatment period. Further studies are needed to examine the impact of the major symptoms on psychological responses, quality of life, and outcomes of the cancer treatments.

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A study on the Diminishing Manufacturing Source and Material Shortages Management Cost Analysis to Select Optimization Alternatives (부품단종관리 비용분석을 통한 최적화 대안 수립)

  • Park, Kwang-Hyo;Shim, Bo-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.4
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    • pp.311-316
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    • 2020
  • The main cause of DMSMS is the rapid replacement cycle and short life cycle of parts, according to the development of science, compared to the long life cycle of weapons systems. In particular, the problem of the supply and demand of such parts becomes even more acute during the operation maintenance phase after the mass production and power generation stage. To eliminate DMSMS problems that arise continuously from development to the operation of weapon systems and select the most cost-effective countermeasures to obsolescence, this paper suggests a standard to determine the appropriate time for quantitative performance improvement by conducting total life cycle cost analysis. For such purpose, this study examined the domestic and overseas cost analysis methods and applied it to single domestic weapon system to verify the research. This study responds to the issue of discontinuing components and helps reduce the total life cycle cost of military products.

TCP10L synergizes with MAD1 in transcriptional suppression and cell cycle arrest through mutual interaction

  • Shen, Suqin;Zuo, Jie;Feng, Huan;Bai, Meirong;Wang, Chenji;Wei, Youheng;Li, Yanhong;Le, Yichen;Wu, Jiaxue;Wu, Yanhua;Yu, Long
    • BMB Reports
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    • v.49 no.6
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    • pp.325-330
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    • 2016
  • T-complex protein 10A homolog 2 (TCP10L) was previously demonstrated to be a potential tumor suppressor in human hepatocellular carcinoma (HCC). However, little is known about the molecular mechanism. MAX dimerization protein 1 (MAD1) is a key transcription suppressor that is involved in regulating cell cycle progression and Myc-mediated cell transformation. In this study, we identified MAD1 as a novel TCP10L-interacting protein. The interaction depends on the leucine zipper domain of both TCP10L and MAD1. TCP10L, but not the interaction-deficient TCP10L mutant, synergizes with MAD1 in transcriptional repression, cell cycle G1 arrest and cell growth suppression. Mechanistic exploration further revealed that TCP10L is able to stabilize intracellular MAD1 protein level. Consistently, the MAD1-interaction-deficient TCP10L mutant exerts no effect on stabilizing the MAD1 protein. Taken together, our results strongly indicate that TCP10L stabilizes MAD1 protein level through direct interaction, and they cooperatively regulate cell cycle progression.

Patients with High Risk Breast Cancer (고위험군 유방암 환자의 치료과정에 따른 삶의 질의 변화)

  • Park, Eun-Young;Lee, Eun-Ok
    • Asian Oncology Nursing
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    • v.1 no.1
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    • pp.32-43
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    • 2001
  • High risk breast cancer patients receive aggressive treatments such as APBSCT in order to prevent the recurrence. These treatments take a long time and decrease the quality of life of patients as a result. The purpose of this study is to examine when the changes of quality of life are dramatic in general and in specific dimension. This is a time series study of two types of treatment groups, in which 15 patients were treated by chemotherapy only and nine patients by auto-peripheral blood stem cell transplantation. Subjects were in this study were stage III and above of breast cancer. Data were collected from April 1999 to April 2000 with the 3 month-interval starting after 3rd cycle of chemotherapy. Data were collected 3 times ; treatment period, treatment finishing period and 3 months later after the treatment. Ferrell's QOL instrument was used which had been developed for the breast cancer patients in 1989. Repeated Measure ANOVA was used to examine differences of quality of life at 3 points of time respectively. As a result, average age was 43.29 years (4.38yrs) and the number of married person was 22(91.7%). Scores of quality of life were 5.45 at 1st period after 3rd cycle of chemotherapy, 5.17 after treatment, 5.10 at 3 months later after treatment and difference of quality of life was decreased according to period of treatment (P=.085). Only the psychological dimension of the quality of life showed the significant difference (P=.045). Two different treatment groups showed a difference of quality of life at 3 month later after treatment. In conclusions, high risk breast cancer patients showed the decreased quality of life related to treatment up to 3 months later of treatment. Subjects who received APBSCT returned to the normal quality of life more rapidly than those who received chemotherapy. Psychological nursing intervention was needed during the whole period of treatment.

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A Study on the Development Type of Component Joint Design for Environment Friendly Multi Housing Remodeling-Living Room (I) (공동주택의 친환경 리모델링을 위한 부품접합부 개선방안의 유형화에 관한 연구(I);거실 및 침실을 중심으로)

  • Lim, Seok-Ho;Kim, Soo-Am;Hwang, Eun-Kyoung;Yun, Mae-Han
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2006.11a
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    • pp.366-369
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    • 2006
  • Multi Housing design has not considered the remodeling even at the beginning of the construction. This severely hindered systematic maintenance, providing fundamental causes of consuming society. In general, in about 20 years when the buildings become too old, they are brought down or removed with a trail of waste left behind. In addition, since the current remodeling or future remodeling type is a general remodeling that leaves only a frame, some question the role of the remodeling as a solution to the reconstruction from economically and environmentally efficient aspects. This study intends to find a solution for long-life span multi-family housing design, promoting sequential remodeling by stating the life cycle of components. Problems were identified by analyzing joints, design and construction of multi-family housing based on the previous researches. Conclusion from characterization of the design plan according to joint parts can be summarized as the following firstly, the problem of the wet was seen in joints between the structure and a finishing materials and ones between separate finishing materials. Secondly, the problem of overlap was frequently seen in joints between the structure and a door/window, ones between a door/window and a finishing materials, and ones between a finishing materials and an electrical/mechanical device.

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